The Samsung 840 series, which is not to be confused with the recently reviewed Samsung 840 Pro, is not really an upgrade to the Samsung 830 series that was released more than a year ago. The new drive belongs to Samsung's new tier; it's slightly slower and has components that suggest it's an entry-level SSD.

That said, it's probably the best entry-level SSD you can find out on the market. This is because the Samsung 840 is not just great-looking but also offers the kind of performance that you'd expect from a more expensive drive. It's an excellent choice for budget home users who want to move up from hard drives for their laptops.

Professionals or those wanting top speed or durability, however, should still stick with the good-old Samsung 830 series, or the new 840 Pro, or any other drives on this top-five list.

The Samsung 840 looks exactly the same as the Samsung 840 Pro. Unless you check the bottoms of the drives, you could easily mistake one for the other. Upon inspection, you'll find that the new 840 series drive comes without the Pro designation and in three capacities of 120GB, 250GB, and 500GB, whereas the the 840 Pro is available in 64GB, 128GB, 256GB, and 512GB capacities.

The new, non-Pro 840 series, however, also comes in the ultrathin (7mm) design and supports SATA 3 (6Gbps).

You can hardly tell Samsung's SSDs apart. From top to bottom are the 840 series, the 840 Pro, and the 830 series.
Dong Ngo/CNET

On the inside, the Samsung 840 series is very different from both the 830 series and the 840 Pro. The 840 series drive uses the new 3-bit-per-cell MLC NAND (also known as triple-level-cell or TLC NAND). In fact, it's the first mass-production consumer SSD that uses this type of flash memory.

TLC NAND is generally slower and cheaper than regular MLC NAND -- which is the mainstream flash memory for consumer-grade SSDs -- and has been more often used for other forms of flash-based storage devices, such as thumbdrives or memory sticks. Technical jargon aside, with the 840 series, Samsung's aim is to bring down the cost of SSDs. The question is, at what level of performance sacrifice? You can find the answer in the performance section below.

A shortcoming of the 840 series is that TLC flash memory generally has lower write endurance than other type of SSD NAND. Write endurance, also known as the program/erase (P/E) cycle, is an attribute that dictates how many times you can write and rewrite information on a memory cell before it won't retain the new information anymore. Because of that, the 840 series will likely become unreliable sooner than other SSDs. This might be why the Samsung 840 series comes with a three-year warranty, compared with the five-year warranty offered with the 840 Pro and the 830 series. The new drive also doesn't comes with capacities smaller than 120GB, since generally with SSDs, smaller capacities also means less P/E cycles.

In real-world usage, this lower write endurance is not really a big issue, however. Per my rough calculations, if you write/rewrite about 10GB of data daily, it would still takes about 7 years for a 250GB Samsung 840 series drive to run out of P/E cycles. Most of us don't write 10GB per day, at least not every day. But heavy users, such as video-editing professionals, should pick a different SSD for their job.

Overprovisioning customization is just one of many handy tools that the Samsung Magician software offers with the 840 series drive.
Dong Ngo/CNET

The 840 series comes in two retail packages: with and without the installation kit. The latter costs about $30 more than the former. The installation kit package includes accessories for first-time SSD buyers who want to have everything they need to clone their existing systems from a hard drive to the new SSD. The bare-bones version includes just the SSD and a CD that contains manual and the Samsung Magician 3.2 software.

The software offers a few handy tools for users to manage, test and customize their 840 series drive. One of these tools is the ability to toggle overprovisioning. The 840 series drive doesn't come with overprovisioning out of the box, leaving the users the options to manage this themselves. Overprovisioning is a feature that enables the use of part of an SSD's storage space to enhance the drive's performance. With the the 840 series, you can reserve between 7 and 24 percent of its storage for overprovisioning, making it one of the most flexible drives on the market when it comes to choosing between speed or maximum capacity.

About The Author

CNET editor Dong Ngo has been involved with technology since 2000, starting with testing gadgets and writing code for CNET Labs' benchmarks. He now manages CNET San Francisco Labs, reviews 3D printers, networking/storage devices, and also writes about other topics from online security to new gadgets and how technology impacts the life of people around the world.